Fluid-actuated inlet valve for rock drills



Jan, 20,

FLULD ACTUATED INLET VALVE FOR ROCK DRILLS c. c. HANSEN Filed Jam 16, 1923 2 Shoots-sheaf. 1

l B INVENTOR mauies (i'Hqzzdcn H I5 ATTO NEY FLUlD ACTUATE INLET VALVE FOR ROCK DRILLJS FiledJan. 176, 1923 I 2 Shouts-Sheet 2 INVENTOR 11 was tffiqnsen.

H45 ATTOR Y Patented Jan. 2t), 1925.

UNITED STATES PATENT OFFICE.

CHARLES C. HANSEN, OF ELAS'ION, PENNSYLVANIA, ASSIGNOR TO INGERSOLL-RAND COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

FLUID-ACTUATED INLET VALVE FOB ROCK DRILLS.

Application filed January 16, 1923.

To all whom it may concern:

Be it known that 1, CHARLES C. HANSEN, a citizen of the United States, and a resident of Easton, in the county of Northampton and State of Pennsylvania, have invented a certain Fluid'Actuated Inlet Valve for Rock Drills, of which the following is a specification accompanied by drawings.

This invention relates to fluid actuated rock drills, but more particularly to a fluid actuated valve controlling the inlet supply, the exhaust being controlled by the piston.

The objects of the present invention are to obtain an inlet valve which is quick and positive in action and will increase the speed of the piston travel, and is-sensitive and effectively controlled by the compression and exhaust from the main cylinder.

Further objects of the invention will hereinafter appear, and to all of. these ends the invention is shown in the accompanying drawings, in which Figure 1 is a diagrammatic view in longitudinal sectional elevation, of so much of a rock drill as will serve to illustrate the invention, with the piston substantially at the beginning of its forward stroke,

Figure 2 is a similar view with the piston at substantially the beginning of its rearward stroke, and

Figure 3 is a similar view of a modified form of valve.

Referring to the drawings and at first more particularly to Figures 1 and 2, the cylinder A of a rock drill is provided with a piston B, having the head C and the forward extension or shank D. The fluid actuated valve E in accordance with this invention, controls the inlet F and a free exhaust port G is controlled by the piston head C. A throttle F is shown controlling the inlet F.

The inlet valve E is provided with the reduced ends H and a single central flange J of larger diameter than the ends H, which flange J controls the passage of motive fluid from the inlet F to both ends of the cylinder A, through the passages K and L.

Small ports, in this instance, indicated as ports 0 and P are for the purpose of alternately connecting the inlet F directly with the spaces Q, and B respectively, at the ends of the valve, which spaces are otherwise preferablyclosed from communication with the external atmosphere, or with other por- Serial No. 613,014.

tions of the machine, so that these spaces in effect, form substantially closed chambers alternately placed in communication with the inlet and exhaust for the purpose of making the valve sensitive.

The faces S and T of the central flange J constitute both actuating pressure areas and holding pressure areas in the operation of the valve, as will hereinafter appear, the pressure either of motive fluid under compression or of live motive fluid against one or the other of said pressure areas S and T of the flange being opposed to live motive fluid in one of the spaces Q and R at the ends of the valve.

The valve may be mounted in a valve chest if desired, in any suitable manner, and in this instance the forward end of the valve chest is preferably permanently closed and the valve bushings U and V are both adapted to be inserted from the rearward end of the valve chest, which is then closed by the back head V, as a convenient construction. The small ports 0 and P are shown in all the figures as extending through the valve itself as a preferable construction and they may conveniently be formed in the central flange J. These small ports O and P are cut ofl by the operation of the valve and al ternately connect the inlet F directly with the spaces Q, and R at the ends of the valve, as a preferable construction.

The valve is thrown by the pressure of motive fluid under compression exerted against one or the other of the faces S and T of the central flange as the piston over-runs the free exhaust port G. When one face of the flange is subjected to compression pressure to throw the valve, the other face is open to atmosphere through the cylinder and exhaust port G. The valve is held by the pressure of live motive fluid on one face of the central flange J, which as stated, is of larger diameter than either end of the valve.

In the operation of the device, let it be assumed that the piston 13 in Figure 1, starting on its forward stroke. The valve is in the position indicated in said figure, and live motive fluid passes from the inlet supply F around the valve, through the supply passage K behind the piston head C, driving the piston forward. The pressure of motive fluid on the face S of the central flange J holds the valve in the position indicated. Motive fluid passes through the small. port P to the other end of the valve, and exerts pressure opposed to the holding pressure and permits the valve to be more quickly thrown on the return stroke of the piston.

As the piston moves forward, and overruns the free exhaust port G, the pressure holding the valve in its" forward position is reduced to atmosphere, through the pas sage" K cylinder A and exhaust port G. The exhaust from the forward end of the cylinder having: been closed by the'piston on its iorwardx movement, compression pressure isbuilt up in front' of the piston and against the forward face T- of. the flange J of theivalve, and isalso built up through the port 0 in the. space Q. opposingithe compression pressure tending. to throw the valve. Thevalve willibe'thrown rearwardly when;thepistonopens the exhaust port G thus relieving the pressure on the; face S of the flange J; At such time the pressure. in. the. space/R: will also be relieved through the port P but dueto the proper size of this p0rt this pressure is not as quickly relieved as-the pressureagainst the faces of the flanged. Thevalve is thrown at the moment that thepressure on the face S'= and in'thespace'Qis-overcome by the opposing pressure, I and this occurs: substan tially at the same instant as the opening of the exhaust as described. The'pressure on the forvvard'face T ofithe centralflange J then holdsthe valve in rearward position; The-cycle is-repeated on" the rearward stroke oflthepiston. By this-construction, the valve is: made sensitive 'to' such a fine degreethat relatively large port areas for operating: a rock drill are obtained with substantially the ininimum practical pressure areas for actuating the valve*.

InFigures 1 and 2 the central flange J of the valveextendsinto the space hetween the-meetingedges-of therva'lve'bushings U and V, so. that/the said meeting edges-form seats for the valve flange and also act as-stops for limiting movement of the valve. By means-of thisconstruction, the valve-is give-n a: minimum travel'with maximum port:area, since it is unnecessary to providefor-an over lapofthe va'lveflang'c at each .sideotthe centralinlet port in the. travel: of. the valve, but the. modification shown in Figure 3 could be used if desired in which the central flange J has sliding contact with the valve bushings and the bushings form stops for the ends of. the valve. Otherwisethe construction of Fig ure 3 is like that illustrated'in Figures 1 and 2."

' I claim:

1. In a fluid actuated'rock drill, the com bination of a cylinder havingan exhaust ort and reciprocatingpiston, a valve chest,

and a fluid actuated inlet valve having a single central flange of larger diameter than the ends of the valve, passages connecting the valve chest with the end of the cylinder, the central flange controlling the passage of motive fluid'from the inlet through said passages to both endsof the cylinder, chambers formed in the valve chest at each end of the valve and small ports connecting the inlet and exhaust alternately with the said chambers in the valve chest at the endsof the valve to admit live motive'fluid to the ends'ol the valve for opposing pressure exertedon thefacesof' the central flange of the valve, and for permitting compression pressure to build up alternately through said small-ports in saidchambers to oppose compression pressure'huilt up on the valve flange.

2. In a fluid actuated rock drill, the combination of a cylinder having an exhaust port andrecip'rocating. piston, a. valve chest, and a fluid actuated inlet valve having a single central flange oflarger diameter than the ends of the valve, passages-connecting the-valve chest with-the ends of the cylin der, the central flangecontrolliing.the passage of motive fluid from the inlet through said'passages to both endsof the cylinder,

chambers formed int-he valvechest at each end'of the valve. andsmall ports extending through the valve connectingthe inlet and exhaust alternately with the saith chambers inthe valve chestat the ends of the valve to admit live motive fluidto the endsof the valve ton o naosingzpressurc exerted on the faces of the central flange of the valve, and for permitting compression pressure to build up alternately through said small ports in said chambers to opposecompression pressure-on the valve flange.

3. In a fluid actuated rock drill, the combination of'a cylinder and reciprocating pi ston, said cylinder havingzafrec exhaust port controlledby the piston, avalvc chest, and a fluidact-uated valve'controlling the inlet supply and having asingle central flange 0t larger diameter than the ends: of the valve, thesaid central flange controlling the passageotmotivefluid from the inlet to both ends-of the cylinder, the faccs'of saidflangc constituting both actuating pressure are-as and'holdi'ng pressure areas in the operation of the-valve, chambers formed in the valve chest at each endof the valve, smallports alternately connecting. the-inlet and exhaust directly with the sai d chambers in :the valve chest at the endsof-thevalveto admit live motivefluid to the endsof the valve for opposingpressure exerted on the faces ofthe central flange, and valve controlled passages connectingv the spaces in the valve chest between the said central flange and the ends of the valve with the ends of the cylinder, whereby the valveisthrown by motive fluid lllll compressed by the piston, and the valve is held by the pressure of live motive fluid on one face of the central flange.

at. In a fluid actuated I'OOlil drill, the combination of a cylinder and reciprocating piston, said cylinder having a free exhaust port controlled by the piston, a valve chest and a fluid actuated valve cont-rolling the inlet supply and having a single central flange of larger diameter than the ends of the valve, the said central flange controlling the passage of motive fluid from the inlet to both ends of the cylinder, the faces of said flange constituting both actuating pressure areas and holding pressure areas in the operation of the valve, chambers formed in the valve chest at each end of the valve, small ports to alternately connect the inlet and eX- haust directly with the said chambers in the valve chest at the ends of the valve to admit live motive fluid to the ends of the valve for opposing pressure exerted on the faces of the central flange, and for relieving said pressure when the valve is thrown, and valve controlled passages connecting the spaces in the valve chest between the said central flange and the ends of the valve with the ends of the cylinder, whereby the valve is thrown by motive fluid compressed by the piston and the valve is held by the pressure of live motive fluid exerting pressure on one face of the said central flange against which compression pressure was exerted for actuating the valve.

5. In a fluid actuated rock drill, the combination of a cylinder and reciprocating piston, said cylinder having a free exhaust port controlled by the piston, a valve chest and a fluid actuated valve controlling the inlet supply and having a single central flange of larger diameter than the ends of the valve, the said central flange cont-rolling the passage of motive fluid from the inlet to both ends of the cylinder, the faces of said flange constituting both actuating pressure areas and holding pressure areas in the operation of the valve, chambers formed in the valve chest at each end of the valve, small ports extending through the valve to alternately connect the inlet and exhaust directly with the said chambers in the valve chest at the ends of the valve to admit live motive fluid to the ends of the valve for opposing pressure exerted on the faces of the central flange, and for permitting compression pressure to be built up in said chambers alternately, and valve controlled passages connecting the spaces in the valve chest between the said central flange and the ends of the valve with the ends of the cylinder, whereby the valve is thrown by motive fluid compressed by the piston and the valve is held by the pressure of live motive fluid on one face of the central flange against which compression pressure was exerted.

In testimony whereof I have signed this specification.

CHARLES C. HANSEN. 

